(ITS#5309) ldap_pvt_thread_pool_setkey_x() addition

Full_Name: Hallvard B Furuseth
Version: HEAD
OS:
URL:
Submission from: (NULL) (129.240.6.233)
Submitted by: hallvard
HEAD has gotten a new function ldap_pvt_thread_pool_setkey_x() replacing
ldap_pvt_thread_pool_setkey() (now a macro), but the change is incomplete.
Fixing thr_stub & thr_debug, they still define ldap_pvt_thread_pool_setkey.
Related: overlays/memberof.c, pool_<getkey and setkey_x> should receive
a pointer to a void variable, not a (void **) cast of the address of a
non-void pointer variable. Otherwise a void* pointer gets stored in a
non-void* pointer instead of being converted to void.
I'll combine another of memberof's getkey() followed by setkey() into
setkey_x() while I'm at it.
Also making passwd.c:slap_passwd_check() and backend.c:be_rootdn_bind()
reentrant: Use setkey_x()/setkey() to push/pop the key=slap_sasl_bind
value instead of setkey()/setkey() to set/reset it.